Manufacturing Meets Purpose: Developing Custom Thermal Monoculars for Diverse Needs

Project Introduction

The thermal monocular is an advanced device widely used in night vision, search and rescue, security, and outdoor activities. To meet the demand for high-performance, multifunctional products, ongoing development focuses on higher precision and smarter features. So the verification of the thermal monocular prototype is critical, especially in the early stages with limited budgets.

CNC machining plays an important role in product development, ensuring high precision, compatibility, and reliable performance. It also allows for quick design adjustments, enabling efficient prototype verification to help companies validate designs and accelerate time to market.

Product Requirements Analysis

Our customer designed a high-end outdoor thermal imaging monocular. The main components of the monocular include a hard plastic shell, lenses, soft rubber eyecup, cushioning eyepiece; metal housing, lens focusing ring, and lens cap.

The monocular project is in the early development stages. Our customer needs 1-3 prototype units for design verification. After the prototypes are approved, they plan to produce 100 units for trial production. Due to limited funding and a short development timeline, they are looking for a professional prototype and low-volume production manufacturer to assist with design verification and production planning.

WayKen’s Expertise in Prototype Development

WayKen has rich experience in prototype production and has provided solutions for over 1000 companies’ new products. We helped to verify the structure, appearance, and assembly of these products. For this project, we are excited to help bring the custom thermal monocular from concept to prototype validation and low-volume production.

Prototyping Solutions for Plastic and Metal Parts

Through prompt communication with the customer, our project manager gained a clear understanding of their requirements.

First, the monocular must be black, with both plastic and metal parts exhibiting no color deviation and a high-quality appearance. Since the product is designed for outdoor use, the surface treatment should enhance corrosion resistance and durability.

Second, while the customer did not specify materials or processes, they sought a solution that ensures quality while minimizing costs for low-volume production.

Finally, as the product is still in the design phase with no defined tolerances on the 2D drawings, trial assembly is necessary during prototype production. The hole and shaft fit are critical for assembly, so we will assist the customer in refining 2D drawings with appropriate fit tolerances to ensure precise assembly in low-volume production.

Plastic Part Processing Solution

Based on our experience, hard plastic parts can be produced using 3D printing to reduce costs and shorten production cycles. However, given the monocular’s precise assembly requirements, we recommend CNC machining to ensure high accuracy.

For deep-cavity parts, a split machining approach followed by bonding is ideal. This method effectively reduces machining costs for thin-walled deep-cavity parts. Although bonding may leave marks, they can be covered by painting, the appearance will still look great.

For soft plastic parts, such as the eyecup, which requires specific hardness, we recommend vacuum casting with PU resin material. The material’s hardness can be adjusted before manufacturing. All plastic parts will use painting to ensure color consistency.

Metal Part Processing Solution

The metal lens focusing ring, lens cap, metal housing, and other tubular components require high surface roughness and external threading. To ensure machining precision, optimal surface finish, and reduced processing time, we recommend turn-mill machining. This allows us to first turn the main structure and then mill the threads for greater accuracy.

For surface treatment, black hard anodizing is the ideal choice, as it enhances wear and corrosion resistance – suitable for outdoor applications. To match the plastic parts’ painted finish, we will fine-tune the anodizing parameters.

For thin-walled metal components, we utilize sheet metal fabrication, reducing processing time and simplifying production. For stainless steel parts, due to the small quantity required, CNC machining with a baked paint finish is the most efficient approach. The high-temperature resistance of stainless steel allows the baked paint to form a durable coating, improving longevity.

By implementing these process solutions, we successfully kept prototype production costs within the customer’s budget while maintaining high part quality. The customer was highly satisfied with our plan, and prototype machining proceeded as scheduled.

Ensuring Precise Assembly for Small Batch Production

During the thermal imaging monocular prototype verification stage, WayKen successfully conducted the trial assembly and assisted the customer in defining precision tolerance requirements for key hole and shaft fits. According to customer feedback, the yellow end of the main housing(picture below) needs to fit precisely with the metal lens focusing ring threads, and the blue end must also fit precisely with other parts. The assembly tolerances for these two areas are critical.

The initial main housing we produced fit perfectly with the other parts. To provide better reference data, we measured the actual dimensions of both ends using a coordinate measuring machine and labeled the dimensions on the side with the 3D drawing for the customer’s reference. They used this data and assembly feedback to create 2D drawings with specific tolerance requirements, which provided effective and practical data for low-volume production.

Feedback and Next Steps

After receiving the monocular prototypes, the customer said, “The prototype verification went exceptionally well this time. WayKen has provided invaluable support, from material selection and process development to detailed production feedback and final trial assembly. You also helped optimize the design for low-volume production. We are now preparing to start small-batch manufacturing and will definitely need your assistance in production.”